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Annotating SQL queries

I have been using oracle and mysql top 10 queries view to proactively diagnose slow queries and optimize them for next release. But sometimes the same query will have different plans depending on data set its executed on. So if you have a sharded database then a query like select * from files where file_path=? and customer_id=? would run fine locally and for most shards but not for some shards.

To diagnose live production issues or issues that occurred in past it would be good to know some query context and one trick to do this is to annotate your queries with context information in comments.

I have a thumbnail generator that launches multiple processes and the correct way to shut it down is to send kill -HUP to the parent process. To automate I had to write a pid file from python, it was a piece of cake
def writePidFile():
pid = str(os.getpid())
f = open('thumbnail_rabbit_consumer.pid', 'w')
f.write(pid)
f.close()

About Me

I like writing good code and improve myself every day by learning new things. I like working for startups as they give you tons of challenges than working for a big company, not sure if you guys feel it but simple programming quirks give me tons of joy. This blog is about the things that I worked on and found worth sharing with fellow programmers who are googling for solutions like me.
This weblog does not represent the thoughts, intentions, plans or strategies of my employer. It is solely my opinion.